Originally Posted by Geist
Yet, plenty of games have taken up these themes and been reasonably successful.

Well, maybe I was a bit unclear here, but I thought it was obvious what I was talking about. I was talking about games that do not only superficially touch on certain topics, but dicuss them in depth, and place them at the core of a games (as Sawyer more or less demanded).

Morrowind was set in a land in the throes of religious strife, whose citizens relied on slavery, while themselves suffering under the yoke of military occupation. It even featured a monopolistic 'corporation' that was corrupting local factions in order to secure exclusive access to valuable natural resources. These are heavy political themes. The Gothics and Fallouts have ventured into similar areas.
A game doesn't have to take place on 21st or 20th century earth in order to deal with difficult issues that humanity has had to grapple with for millennia, that we face today, or that we might have to tackle in the future.

Here I very much disagree. You cannot talk about something without naming it. You can of course use a political, social, or religious theme and implement it on an abstract level into your game. But I'm not sure if that would do justice to reality. I have the feeling that on such a level simplification is almost unavoidable.
Keep in mind that we are not talking about moral choices here…